The Arctic sea ice melt season grew longer for decades, but something strange happened around 2010

For most of the satellite record, the Arctic sea ice melt season kept getting longer. Around 2010, however, that long-running trend unexpectedly flattened.

For decades, Arctic sea ice generally began melting earlier in the spring and did not freeze again until later in the fall. Together, those changes extended the annual melt season and contributed to major losses of sea ice across the Arctic.

A new NASA-led study now finds that although the melt season has lengthened dramatically since satellite monitoring began, its average duration has changed relatively little since about 2010.

Arctic Melt Season Is About 40 Days Longer

The researchers found that the Arctic sea ice melt season is now about 40 days longer than it was in 1979.